Turbine



1,469,925 A. T, KAsLEY TURBINE Filed Dec. l2, 1921 3 Sheets-Sheet 1 FHL/ l WITNFSSF?, JL INVENTOR SYM ATTORNEY AIF. Easley A. T. KASLEY TURBINE Filed Dec. 12, 192i s sheets-sheet s I vll lll I AOT INVENTOR ATTORNEY 'remise oa. e, icas.'

'wafers ALEXANDER fr. EASLEY, or vrssrneron, :e`ENnsv'iiviiiira,Y assrenoa'ro WESTING- HOUSE ELECTRIC aiaanurac'ifoiiine COMPANY, ii coaronarro'n ori PENNSYL- y valira.

TUEBINE.

Application filed December 12,1921. Serial No. 521,872.

To all whom t may concern: f y

Be it `known that Il, ALEXANDER TKASLEY, a citizen ofthe United' States, Aand a yresident of Essington, in the co-unty of `Bela-ware and State of Pennsylvania, have invented a new and useful improvement in Turbines, of

whichthe following is aspecication, this application being a Vcontinuation inpart of my application,Serial No. 486,517, filed'V July 21,1921'. l'

My invention relates" to steamv orA elasticfluid turbines, and more particularly to lowpressure blading of the..relativelywidetype which receives steam orjelasticfluid later` ally and discharges it peripherally, yand it has for its object to prov-ide low-pressure blading ofA this character which shall Ybe so designed astoloperategwith-little, it any,

vibration -or deformation duel to centrifugal bending stresses andwhichjshall becapable of being easily and cheaply inanufactured.'l

-Y further obj ect oi' my ,invention is to provide, in vconnectiony with blading of the character` designated, meanslfwhich shall deliect the steamer elastic fluid 'froman axial toward a radial direction vand which shall reinforce the blading structure. Y 1

inthe drawings, forminga part of this application, :is a sectional viewof a turbine with one form of my improvedblading applied thereto;V Fig. 2; is a' perspective view on a larger scale'oil one of the blades shown in Fig. 1 Figs.A 3, l4L and 5 are sectional views taken along the linesIII-IH,v

V-IV and V-Vrespectively of Fig. 2; Figf is a detailed viewfshowing a slightly modified ,forni or" blading; Fig. 7 isl a view similar to Fig. 1, but showing a modified form of low-pressure blading; Fig. Sisa sectional Aview` taken Valongthe line VIII- VIII of' Fig. 7 and viewed in the'direc-` tion of the"V arrow;: Fig. 9 isa view similar to Fig. -l,but showing astill'further modified form kon my improved low-pressure bladingyFig. 10 is a detail view ofy a portion of the blading structure employed in Fig. 9; and Figsll and 12 are',- diagram-l matic views illustrative of certain' features of my invention. 'A y In the construction of steam or elastic fluid turbines,particularly of 'the `large high-speed type,v itV hasr heretoforefbeen found to be necessary tolpro-vide'the last row or group-.0f rows Gf :moving blades With large leaving angles in ordefrto handle the large 'volumesof low-pressure.' steam or ela-stic luid forthe reason that, for a given speed, the blade height is limited Vby the al- 'T i I lowablestress ofthe material-of which the Vblade -is made; and, of course,jas the leav-V ing.l anglesare Vmade larger the leflicie'ncy kof the blading declines In the-constructionof high-power single unit turbines, diniculties haveg'beenfinet .withV on account of excessive blade speeds due toV theflarge rotor or v'disk diameter and the last row oftall niovinglblades necessary to pass the elastic fluid the latter is to be disf charged without tofo much residualenergy. r*

In the application of vHenry .F.f Schmiduerial No. 482,768," filed-July 6,- 1921, .and,`as-

siUned to the Vlfestiiighouse'Electric-fand" Manufacturing Company, Athere isdisclosed and claimed krelatively widelastrow blad;

ing which Adischarges peripherally or peripherallyand laterally, vthereby making it posA- sible to increase'.I the exit area -byjincreasi'ng the blade width instead of the bladeheight, f

as forinerlj, and making possiblefto pro-` vide high-'power turbinev units without en oountering excessive bla-le speeds. The-blad ing .disclosed and claimedinsaid application of Henry F. vSchmidt is "relax tivelywide audit" is capable .of handling' large volumes of low-pressureelastic,fluid or steam'gand vof discharging the latter at small angles, thereby resulting in' high blade elliciency, inf-improvedv turbine performance, i

andfin' makingV .it` practicable vto construct large, highspeed turbines which` operate withhigh eilicijency. In the Schmidtturf bine, Vadeolluate discharge' area at smallleaving vangles is provided 'by-having the steam 'Y or, elastic fluid discharged peripherally or' discharged perphemui S0 that adequate discharge area-v. may be provided, with 'the preservation @t efficient' discharge @Heils-S.;

vi'oo the blading, whereas, with axial-flow blad-v vmerely by choosing a proper width. It will be obvicusthat a change inv width is not acL companied by'any change in uni-t stress in ing,can increase in the discharge area isl securedl loy'maliing` the. blades taller or byl choosing largerdischargeiangles. As axiallow blading is made taller the centrifuga-l stresses increase until a point is Vreached be` yond which it is not saire to go and' further.

rdischarge Yarea may be provided only by K gauging or providing'lthe Vblades with larger discharge angles which produce less eliicient bla-ding for the reason-that the 'larger the discharge angle thelarger' beconiesV the axial component or'v thefreactiv'e effort, The capacityvof aXial-iiow blading' to handle large volumes of elastiei'iuid eflci'ently V'is liniited which is not true ofk blading ofthe-wide type disclosed hereinfand in theS-chmidt application aforesaid'.A Since wid-'th is amaterial factor in providing adequate discharge area i V`with' the latter type of'bladin-g, it is t'o be f understood thatfthe terms wide and relativelywideL are used inl this specification 1 and thev'appeiidedclairris'to designate blad@ j ing of' this n character' Vwhich differsr markedly over' aXia'llflow bladin-gf hereto-fore used. "'lh-is type of blad'ingis also capable or con ver'ting a greater' portion for' Vthe vkinetic energyo'f the elastic fluid or steam into useful work than can be c'zonveiited'` by hlatlingof the ordinary/,type or'the reason that, with the peripherally-dischargingtype or blading, the'reacti-ve force or effort is applied to por tionsr of the bla-ding moving at high e'ilective blade speeds. i

l A. lt is the objectv or"- `my-intentionto iniprove the type oi low-'pressure blading disclosed in the application or Henry S. Schmidt, aforesaid, so that it may be more easily and cheaply made `and may be of such a design as to secure better operation. The contour ofniy iniprovedblade is such that it maybe easily rolled or dropforged, or a row of'blades inay'be builtup of laminae or sections and secured together in any 4suitable manner. Better operation is secured by Vso designing each blade that'tlie center or" Vgravity thereof falls approximately midway I invention, in Fig. 1, I show'a turbine coinprising a cylinder or casing 10 having bearings 11 of any suitable type for appropriate journal portions of the rotor 12. Any

l suitable energy-abstracting elements are carried by the casing and rotor yfor abstracting energy by theexpansion of steam or elastic iiuid, For' example, I Vshow a stage or the Iiiultiviel'ocityv impulse type, comprising series of fractional expansion stages coniprised by the stationary and moving Vrows* of blades' 1.7 and'v 181 Ycarried Yby the cylinder or casing 10 and by the rotor 12, respectively. The steam orjelastic fluid undergoes 4impulse blades or buckets 16, followedlbyl a "ItV pressure-velocity conversioninthe `nozzle-lor Y `nozzles 13' and the velocity energy-s-ab# stracted in two steps by' tlie'inipulsefb'lades orbuckets"lill and 16. Thereattemthef steam is fractionally'expanded 'in the stages;coni"-V prised the stationary and moving rowsl'or .blades 1 and18,and the steam then passes from the' last row of' movingl bladesi 18 atv a low pressure for action upon the bladinggot my Vimproved form! of low-pressure stage'l? comprising a row ofi guide blades-20 carried bythe cylinder or casing-10 and ai row of relatively wide bladesf 21 carried "by-the Irot`or12.;

The guide blades 20 discharge stearn- 'or elastic iuidf between the'bladesf 21 andthe.

steam or elastic iiid'is discharged fromr the latter peripheral-151er radially and-laterally orr axially. Each blade 21 has" an inner ra# dial orplane portion 22; having: a suitable i root portion 23 ror'attaclment tothe rotor 12. fThe radial or plane portions! 22 rarearranged in' approximately 'axial planes and constitute supports for 'the outer `curved, 'spoon-outline, ortrough-likej 'portions 24. constitutingenergy-abstracting portions for the blades.V Thecurved, spoon-outline, or trough-like portions 24. exten-d fromithe in.

let sides of the blades across lthe tops thereof, around the rear"corners,and thence inwardly; and, as illustrated in Figs. vk1 and 2, the inwardlyfeXtendin-g portions 'may Vmerge into the inner' radial portions 22, al-

though it is to be understood that the'inwardly-e`xtending curved portion' may eX- tend inwardly to any desired extent. This forni or curved *spoon-outline, or trough-like .constructionV permits *of` the discharge of vsteain or elastic fluid bothperipherally arid laterally at small angles. f Y

' As shown in Fig. 1, the casing or cylinder 10 isprovided with aportion 25 which, not only constitutes a support for theguide blades 20, ybut also serves ,toy cover the outer portions of the inlet'sides of. the trough or spoon-outline portions 24 deiining nozzle expanding passages between the blades, thereby preventing the cross-flow of ksteam or elastic fluid inte the latter passages.' A suitable plate 26 is' secured to the rotori12- and is arrangedto cover the rear radial portions o the blades' 21.

'v Each of the blades '2.1 is soy `designed that i its center of gravity falls substantially midway of the thickness thereof,thereby avoiding the developmentof centrifugal bending stresses which might tend to cause itto vibrate or be deformed.

' The inlet edges 2l of the blades 21 may be suitably inclined in accordance with the blade velocity, steam, or elastic fluid velocity, andthe angle of disch'arge'of the steam or elastic-fluid from theguide blades 20. See.

rigs. 2, s, Li, and ii.

Referring to the velocity diagram show-ii in'Fig. ll, tlievector a represents the v elocity and direction of discharge of motiveV fluid leaving the guide blades20, the vector o .represents the blade velocity, and the vector c represents the relative velocity of the motive fluid with respect to the blades 21. The inlet side 2l should, therefore, be so curvedas to be ,tangent to the incoming motive fluid, that is, to the vector c. In other` words, the curvature of the inlet edges of the wide blades 'is determined bythe direction and velocity of discharge 'from the guide blades and by 'the velocityof the mov-A ing blades. Y

lnv Figo, Ishow a modified form of Vmy blading in which the curved, orA spoon-outs line outer portions define expanding pas' sages 27, a throat being indicated at 28,

- porting'portions 3l arranged in axial planesv and aoapted to be'secured to the rotor 12 by anj,T suitable root connection 82. Curved, or spoon-outline portions 38 are carried at the tips of the blades 8O and vciooperate'to deline nozzle or expanding passages' for the lpurpose of abstracting energy from .steaml or elastic fluid passing therethrough. Steam or elastic iluid is discharged between the'infV `let edges of the blades 80by means of guide blades '20 in the mannerheretofore described.

As the steam or elastic fluid enters between the blades 30 of Figs. V7 and 8 in substantially7 anv axial direction Aand vis discharged therefrom` at the tips or periphery,

I it is desirable to provide deflecting means to secure a change in direction of flow of the steam with a minimum degree .of eddyin'g. Accordingly, I have provided each blade with a series of ribs 34 carried by the faces of the radial portions 8l. Preferably, these ribs are made of c urvedangle sections secured to the radial or plane portions 8l of the blades infany suitable manner, las `by spot-.velding, The angle guide membersor ribs 34 are provided withangleportions which are adapted to contact, as shown in Fig. 8, to constitute partition or wall ele-V ments in order to divide anddeflect'the steam or elastic fluid for discharge through the passages defined by the curved, or spoonoutline portions 38;. and, in order that the portions )35 Vymayfcontact throughout the lengt-hs of the Vguide members 34, it is ne`cessary tliatsucli portions 35 Ashall be made oftaperingwidth on account of the radial `divergence of `the blades.

The portions 36 off the guide members 34 arel adapted `to be.;

blades in order to hold the guide members 84: in place. The guide members 34a-re spot-welded to the blades'SO before the latter are assembled. f v Y In Fig. 7the cylinder or. casingflO is provided rwith a portion 25/which'not only supports `the fixed guide blades 20, but also covers the outward portions'of the curved, or spoon outline portions 33 inthe -manner and for the purpose described in connection' with Fig. 1':

' In Figs. 9v and V.l0-,fl show afurther-inodi.

lied form of wide blade 37 forfthel last stage '19.Y The wide blades 37 are' composed of a plurality of laminations v88,'hav-ing blade-1 por# forming portions 89' and hubforming tions 40.- 2 The laminations 38 may be punched from any suitable sheet `metal, either as single pieces orin sections laminations are piledtogether lengthwise of the rotor 10 so that`r the-blade forming portions 89 y'register to constitute 'the wide blades 37.1 The blades 37 comprise inner radialsupporting portions il and outer curved, spoon-outline, or'troughdike energy*v abstract-ing portions 42, arranged vsimilarly to the corresponding. portions of Fig. 7; fln

'spot-weldedfto the radial :portions 31 of the The.y

order to prevent side-spilling of steam or Y elasticffluid from the blades-*37 aiidvto as# sure the change in direction thereof so that it may be discharged peripherally, it isfnecfk essary' to block the 'spaces between vthe blades; and, I have', thereforeprovided a suitableA blocking plate forthis purpose. j

The laminated. construction is -advantageous in thatit is possible to build up a blade structure of any suitable width economically and for the further .reasonthat the resulting structurels st rongeras the blade-forming portions '39 are integral with the hubforming portions 40,' thereby avoiding the Y use of ordinaryA root` connections. in all of the niodilicationsaforementioned high blade -efiiciency is maintainedl bythe preservation vof -smallf4 dischargewangles. This willbe apparent from diagrammatic Fig. l2, whereinthe line d, tangent to the inner Aedge of `the outer. portion of the' curved lor spoon-outline portion, represents the direction of' discharge of motive fluid and the line fc is the tangent to the blade;

' be noted kill.. s

4tip circle The .angle of between the vlines d and e 1is he angle of discharge and'it will that it is relatively s niall.

Apparatus inade in accordance with my fluid is expanded the hi her oresgos et tha-.turbine and it is dissu're stage i9, liaviiigthe relatively Wide rov.'v` oiireaction bladigng vwhich re- Hl ce` ie su n or elastic fluid flowing in' sl rallyV mi direction and distion vor j aeripherall-y and, laterally. The stea-ni or elastic thi-id is expanded and d -ischarged f trointhe nozzle passages, defined bythe curved spoon-outline,l or -trouglnlilre portions of the Wide blades, atsllnll angles', the 'feature ot' discharging'- :at small angles being Vliossible due to the tact that the disf charge arca niay be inade suiicient merely bychoosinfg suitable Width of blade.

lt will be obvious to those slr-il-led inthe art thatniy neu"A type of .blade is capable Voi securing betterturbine operation. My

newbladesare capable yof handling large volurnes of low-pressure, elastic ilu-id or steannwoif expanding` ,theV elastic fluid orY l steam to low-pressures, oi operating at high lade etciencyas the elastic icl-'uid orsteani is discharged at small angles andthe reac- Y instead of height,

4tive effort ci thehigh velocity elastic vfluid or steani is applied to the blade portions moving at highfetl'ectivespeeds, Iand 'ot operating'at highY speeds as the discharge area is secured-by increasing the blade Width Byusing my Wide .eirhaust bleeding, itis thereto-re possible to construc-t large, Vhigdi-speed turbine units and units which operate more .elciently Vvthan heretofore.

'While l' have shown: rny invention in .a plurality oic torins, it will beobvious to those slrilled in the artthatiit is not soliniited .but is susceptible Voi variousv other changes and niodilioations without departing troni the spirit gthereot, and l desire, therefore, that only such limitations shall be placedtliereupon fas are imposed by theprior ,art oras are specitioially vset forth in ,the "appended claims. A i i What l claiinis; t i l. ln an elastic-fluid turbine,' a last rorv Vot moving bladesy having inner radial or plane `portici-is and outer curved portions adapted to receive elastic fluid axially and tov discharge it. peripherallylaan elastic-fluid turbinefa Yrow of peripherally-discharging nioving 'blades adapted to receive elastic iluid atone side,

kthe center of gravityo each blade being j disposed symmetrically with respect to the circumferential distribution of niass thereof.

"3. A turbine blade a radial por` tion and acurved tipdischarging portion, l

on operates as tol-lows: Stefani or Vcnarges itgperipherally erin a radialV directhe center otgravity of Vthe blade falling With-in the radial portion.y f

d. ln Van elasticftluid turbine, aroW ot peripherallydischarging blades having inner radial VportionsV and outer vcurved portions to provide :tor the discharge ot elastic fluid :at a small angle.

5. ln an elastic-fluid turbine,varro\v oit perifpherally-discharging` blades having inner radial portions and Vouter `curved,portions arranged to discharge elastic fluid at a small angle, and elastic-Huid or .steani 'detlectingi Vmeans cooperating with the'radial portions energy-abstractingportion at vthe tip.

Y 9. Auturbine bladel comprising anr inner radialA portion and an outer Yspo oii.outline or trough-like por'ion, vthe centerolg gravity `@Lt the blade falling Within the-radial portion.

kl0. A turbine lblade comprising` inner radial and an outer"spoon-outline or .troughlile portion, the center of V Q.;ravity .ot the blade falling -inidway ol? thethiclrness of the radial portion .of the blade,rwhereby centrit'- ugalbending moments are avoided.

11. ln. inelastic-fluid turbine, ya last row of moving blades, each comprising? line or trough-like portion, the kouter poran iii-'- ner radial portion and-an outer spoon-out-" substantially plane portionA andV al curved,

Yioo

tions of the spoon-outline or trough-like f portions defining passageway/rater theV er'- Vpansion of elastic vifi-uid peripherally'.

1 12. Inl an elasti c-uidA turbine, alast ron of "movingblades havingv energy-abstracting outerj Vportions l inner '.supporting` portions therefor secured in'position substantially in axial planes. y

13.' ln an elastic-fluid turbineghaving' a rotor, a" last row ot nioving blades having energy-abstracting outer portions and 1n-.

ner supporting; `por-tions arranged substan-v tially in axial planesand secured v'to said vrotorthror-.gliout the rvidth ot said inner portions. A i

14. lnfan elastic-fluid turbine 'having arot-or, alast row of inoving blaA s having outer, peripherally-Y or tip-discharging energy-abstracting portions carried fbjf inner portions-arranged in Vsubstantially axial planes and secured throughout the Width thereof to said rotor. Y 1 i l5; ln an elastic-fluid turbine,` the ooinbinatio-n of a last row ot blades adapted to receive elastic fluidv at one side and to discharge it at the tips, each blade having an outer curved portion to provide for the discomprises an outer curved portion and anv inner substantially plane portion, and rib or partition means secured tothe plane portions and 'suitably curved to assure the change in direction of elastic fluid received at one side of the blades for discharge at the tips. V

l?. In an elastic-fluid turbine, the combinetion of a row of blades adapted to receive elastic fluid at one side and to dis-l charge it at the tips thereof, each blade comprising inner substantially plane portions and an outer curved portion and the massV thereof being so disposed that its center of gravity Vfalls tially midway thereof, and similarly placed guide ribs secured to opposite sides of' each blade, the guideribs of adjacent Jfaces of adjacent blades cooperating to define partition or wall elements to secure a change in direction of elastic fluid received Vat one side of the blades 1for discharge at the tips.

18. In an elastic-fluid turbine, the combination of a row'of -blades adapted to receive elastic fluid at one side and to discharge it at the tips, each blade having an outer curved portion and inner substantially plane portion, and contacting curved guide 'ribs spot-welded to the inner ysubstantially plane portions. Y

19. In an elastic-fluid turbine, the oombination of a row of blades adapted to rea ceive elastic fluid at one side and to dis-l charge it at the tips, each blade comprising an outer curved portion to provide for the discharge of elastic duid at a small angle Vand an inner substantially plane por-v tion, and guide members of angle-form spot- Vwelded to the blades and contacting'to define partition vor wall elements adapted to secure a gradual change in direction of lpartition member.

, substanelastic Vfluid sovthat it toward the blade tips.

20. In `an elastic-fluid turbine, the coinbination of a row ofblades adapted to receive elasticfluid at one side andvto dis charge/it at the tips ,and contacting and curved guide ribs spot-Welded to the blades may be discharged elastic iiuid so that the latterimay'bevdischarged toward the tips of the blades. 1

2l. In an elastic-fluid turbine, the com- -to assure a gradual change in direction of bination of a row of blades adapted to receive elastic'tluid at one side andto. discharge it at the tips thereof and curved anglermembers, each of which has one angle portion spot-welded to a blade and the other angle portion serving as. a` guideor 22. In an elastic-fluid turbine adapted to discharge elastic fluid transversely to *the direction in which said fluid initially ows therein, the combination 01' a last row of -bladesadapted to receive elastic fluid atV one side andi to dischargerit at thetips there-y of and ribs carried'by the blades'to assure thegradual change in direction ofelastic fluid passing therebetween. 1

' 23In`an elastic-fluidturbine adapted to discharge. elastic `fluid transversely to'` the. direction in which said fluid initially iiows therein, 'the combination of a last row of blades adapted toreceive elastic 4fluid at the sides and to discharge itat the vtips go thereof and ribs carried bythe blades and adapted. to constituteip-artition or wall elements therebetween, whereby the direction of flow of elastic fluid is `changed and the blades press each other.

24. In an elastic-,fluid turbine, the com-1 bination of a rovs7 of blades adapted to receive elastic fluid at Vone side and to discharge it at the tips thereof and contacting ribs carried by the blades to assure al change in direction of ow of the elastic fluid and to reinforce the blades.

25. In an elastic-Huid turbine, the com'- 'i bination of a row of blades comprising innery Vradial portions and outer curved vportions to discharge elastic rfluid peripherally" at small angles and contacting guide members carried by the blades Vfor deiiectingy `the elastic fluid and'bracing the blade structure.

In testimony whereof, I have 4,hereunto subscribed my name this 7th day of De-` cember 1921. Y

f ALEXANDER T. KASLEY. 

